Breastfeeding, lump, biopsy, mastitis, confused

Hi all- I am a new mom, have been breastfeeding for 3 months. A month ago I found a grape sized lump on my left breast (no pain), thinking it was a clogged duct, I tried all my usual tricks and it didn't budge. Two weeks later, I went in to the ob, she said it was likely a clogged duct, but would order an ultrasound for my peace of mind. The ultrasound found a mass that did not look "too suspicious". Oval shaped (non spiculated), lymph nodes looked fine. Since I am lactating the radiologist suggested imaging three month later and said it was likely a lactating adenoma. I had a lot of questions and ultimately, was given the option of a biopsy, which I took. I've lost several family members to cancer and know early intervention is key.

I had a vacuum assisted core needle biopsy last Friday 11/5, results were in this Monday:

Core biopsy of left breast 10:00, 6 cm from nipple:

- Acute and chronic mastitis with granulation tissue and

foreign body giant cell reaction.

- Portions of lactating breast.

This is benign and concordant with imaging findings.

> Recommend appropriate therapy treatment in the setting of acute on chronic mastoiditis. Return to risk appropriate screening.

I have no idea what this means, my doctor is saying mastitis and prescribing 14 days of antibiotics, but I have no systemic signs of infection- no fever, chills, etc. My milk supply is also stable (left breast produces twice as much milk actually)

Since the biopsy, I have developed skin thickening at the biopsy site/ surrounding area, and the lump feels larger.

My left breast has also always been slightly larger, but as of a month ago it is now noticeably larger.

I am not sure if this is something I should keep aggressively pursuing, or just go with the 14 days of antibiotics and re-assess then. From my research something like IBC is usually missed at first and I am terrified something was missed.